Humidifying system and apparatus



March 10, 1953 G. B. HOLTZCLAW 2,639,972

HUMIDIFYING SYSTEM AND APPARATUS Filed Feb. 1, 1949 2 SHEETSSHEET 1 afiovea B. 110222021210, by MJM Min-M 46 64 039 7s 7p Q6 6; e3 6% I 76 e7 66 em 2 69 49049 9 34 5/0 :2 4 e0 66 7o 7/ March 10, 1953 cal B. HQLTZCLAW 2,630,972v

HUMIDIFYING SYSTEM AND APPARATUS Filed Feb. 1, 1949 SPEETS-SI-IEET 2 Patented Mar. 10, 1953 HUMIDIFYING SYSTEM AND APPARATUS Grover B. Holtzclaw, Charlotte, N. 0., assignor to Parks-Cramer Company, Fitchburg, Mass, a corporation of Massachusetts Application February 1, 1949, Serial No. 73,910

8 Claims. (Cl. 236-44) '1 vThis invention relates to improvements in system and apparatus for humidifying the atinosphere of a room or other enclosure by atomization of water within the enclosure.

Usual systems for conditioning the air of an enclosure by vaporization of water therein comprise installing a number of vaporizing units such as atomizers suitably distributed throughout the .enclosure and turning on the units at full capacity until the humidity of the atmosphere of the enclosure reaches a predetermined point, then turning them full off until the humidity of the atmosphere is reduced by liberation of heat in the enclosure, or otherwise, to a predetermined lesser condition of humidity. This has caused uneven ,conditions as the atmosphere would be alternately over humidified and'under-humidified.

Various control means have been tried for lessening the extent of such irregularities in the humidifying cycle, such as the graduated and.

multi-step control devices outlines by Karlson in Patent No. 1,729,074. Improved humidifiers of the self-cleaning atomizer type operable by both air and water under pressure have been developed,

.such as shown in patents to Simon No. 2,362,102 and Holtzclaw No. 2384,679, such humidifiers being particularly suited to graduated control for varying the rate of output of moisture in accordance with variations in the humidity and temperature of the space to be humidified. To date, however, the use of these improved atomizers has been hindered because of the lack of development of suitable controlling means.

The present invent on goes much further than heretofore by combining certain of the best features of previously developed atomizer humidifier systems including automatic control instruconditions such as prevail in a textile mill or other industrial establishment where controlled humidity is required, and continuously varying the moisture delivery of the un ts in correlation to the requirements for humidity of the atmosphere of the enclosure to produce a more clearly fixed level or close range of humidity in the enclosure, and only to interrupt the continuous supply of moisture when, with the output of the humidifiers reduced to the minimum for satisfactory and economical operation, the humidity of the enclosure begins to exceed the upper limit of said f close range.

A further object oitheinven'tion isto provide improved control means for utilizing the variable output feature of atomizer humidifiers of the general type shown in the Simon and Holtzclaw patents above referred to, so that under normal operating conditions when maximum output of the humidifiers is not required, the humidifiers may be made automatically to operate at reduced output insuchmanner as to producea finer atomization of the water and wider dissemination thereof within the enclosure than is secured when less improved control means are utilized.

A more specific object of the invention is to provide a system of the character described with the main regulating instrument of such extreme sensitivity and quick response to changes in atmospheric conditions within the enclosure-that it will continuously adjust the supply of moisture in correlation thereto before any appreciable change in the condition of the humidity within the enclosure has occurred. I

A further specific object of the invention is to provide a humidifying system having conduits for supplying air and water under the same or correlated pressures to the moisture supplying means with a main and a supplemental valve in the conduit which supplies air under pressure to the system, with automatic controlling means acting in response to a small deficiency of humidity of the atmosphere below a predetermined standard, first to open the main valve, thereby to permit control of the humidifiers by the supplemental valve at very low moisture output and thereafter, if the deficiency in humidity increases, gradually to increase the opening in the supplemental valve to cause gradual increase in humidifier output until humidity begins to rise, ,upon

which the opening in the supplemental valveis gradually reduced and humidifier output is correspondingly lessened. In this way the output. of the humidifiers may vary through a. very wide cycle during a period of widely fluctuating re.-

quirements, always keeping the resulting range of variation in humidity of the'atmosphere within narrow limits. Also by using the highly improved automatic humidity regulating instrument of the type described herein which is sensitive to minute fluctuations in humidity of the atmosphere to which it is exposed, the output of the humidifiers may be graduated so closely that under conditions of nearly constant moisture demand the humidifiers will continue to operate at fixed or nearly fixed output for long periods in sharp contrast to the onand ofi operation or the widely varying output of other systems less highly perfected.

These and other objects and features of the invention will more fully appear from the following description and the accompanying drawings and will be particularly pointed out in the claims.

An illustrative embodiment oi the invention is shown in the accompanying drawings, in which,

Fig. 1 is a diagrammatic view of a humidifier system embodying my invention;

Fig. 2 is a front view of an improved type of regulator for controlling the main and supplemental valves, the front door being omitted to show the wet and dry bulb thermosensitive elements and the valve mechanism operable.there- Fig. 2a is a horizontal sectional view" on line 2a-2a Fig. 2;

Fig. 2b is. a. detail. view of a modified connection: between. the lever: which; is actuated by the wet bulb element". and" the. bar which controls the conjoint action. oi the. wet and. dry bulb. ele. ments;

Fig. 3: is aside. elevation of the regulator illustrated in- Fig. 2, showing the manner in which the moisture is supplied to the wet bulb element;v

Fig. dis avertical sectional view online 4'-& Fig. 2,. showing, the dry bulb compartment, the thermosensitive element contained therein, the mechanism operated thereby being omitted, and illustrating the manner in which a separate current ofair from the enclosure to be humidified is introduced therethrough at suiiiciently high velocity so that actuation of the dry bulb element' will beprompt and accurate; and,

Fig. 5 is a diagrammatic view illustrating the mechanism for controlling. the operations of the main and supplemental valves;

The system for vaporizing water within an enclosure with means for regulating the same, .embod'yingthe invention as shown conventionally in the drawings; includes a horizontal air line i, which may be. provided with suitable horizontal branches, suitably supportedinthe usual mannerin the upper portion of the. enclosure to be humidified; Usual means,.suchasan air compressor, not shown; isprovided for. supplying. air under suitable superatmospheric. pressure to the air, line i. Atomizers 2,. preferably of the type disclosed. in. Patent No.. 2,384,679,111 which the atomizersare supplied with. water and air under the same. or correlated pressures, are mounted on. the air line. I. at suitably spaced intervals throughout. the. enclosure. The airline l extends from the pressure-supplying means through control valves 13 and Hi to theatomizers land also communicates with the upper end or a water tank or other suitable enclosed container. 3. A water pipe 4 which leads from the tankbelow the water. line thereof extends upwardly and thence horizontally in parallelism with the air line I and is provided with vertical pipes 5 leading toth'e several atomizers. Suitable means are provided for supplying water to the tank 3 under somewhat higher pressure than that of the air in order to permit the tank to be properly filled. As illustrated the pipe 6' from a suitable main or other source of supply delivers water under pressurethrough a water feeder l which is socured to the side of'the tank 31 and communicates with the tankto maintain a predetermined water 'leverthereim A float-valve 8- withinthe chamber of the water feederycontrols' the: entrance of water from the pipe 6. As a further protection in maintaining water level within desired limits, a

supplemental float valve 9 mounted on extension I izers so that the water pressure at the atomizers is at. least. slightly lower than the pressure of the air which is supplied to the atomizers through the air pipe i, thus insuring that only atomized water will issue: from the atomizers and that a no drip will occur upon shutting off of the air pressure. However,, the tank or other enclosed water container may be located in any position to. provide the same water pressure as that of the air line or a desired pressure correlated to thatof the airline.

It. is to. be emphasized that the method and.

apparatus for controlling water level herein described are merelyillustrative. As far. as the inventionis concerned, the point of importance is that water levelbe. maintained substantially constant, and at a level with reference to the out"- let of the humidifiers which is; suited in each particular installation to the type of humidifier used and other. requirements peculiarto the: case at hand.

An. automatic. humidity regulator 12, as shown in Fig. 2, controls the air supplied to the atomizers through two diaphragm valves 13 and M in the air line. i. The main valve 13 is operated by the regulator to full-on or'iull-off'positions while the supplemental valve I4 is. actuated by the regulatoron a graduated basis.

As illustrated in Figs. 2, 3 and 4, the humidity regulator I2, which is an improvement over previous humidity regulators of the same general type as shown in Patent No. 1,819,987 to Hodge, includes separate compartments for wet and dry bulb elements and it will be seen that both wet and dry bulb compartments are shielded from each other and from the main frame of the instrument by the double wall construction with insulating space between.

The dry bulb compartment I6 is contained in 'a' rectangular casing ll" insulated by the surrounding air through which is guided a sample current of air from the room or enclosure. A rectangular projection I8 of easing i1, which extends through the back 19' of the regulator, provides an entrance for the air into the casing, Where it thoroughly surrounds the thermosensitive element 23, thenpasses downwardly and outwardly through the back i9 of the housing and then outthrough a downwardly extending L 20. The sample of air is induced from the enclosure through the dry bulb compartment by an air nozzlev 2| in, the. L which is supplied with air under pressure from a suitable source which blows downward through the outlet 22 of the their response to changes in temperature of the air to which they are exposed. The dry bulb element is mounted on an arm extending from one end of a horizontal bar 24 which is attached centrally to the back of the main regulator housing. This supporting bar, which also carries the web bulb element, and its extension 24a, which carries the mechanism above is made of invar steel or other material having a relatively low coefficient of thermal expansion in order that the operation of the device as far as possible will be aflected only by the action of the thermosensitive elements.

A vertical rod 25, which is connected at its lower end to the center of the top of the dry bulb thermosensitive element supports at its upper end a weighted lever 26 which is pivotally mounted upon a bracket 21, secured to the integral upward extension 24a of the bar 24.

The wet bulb compartment consists of a similar insulated casing 29 through which is guided a separate and entirely independent current of air from the enclosure. This air enters from the top, the flow being induced by the action of a humidifier 34. The flow of air through the wet bulb compartment is sufficiently slow and the spray from the humidifier 34 is sufiiciently fine so that the air becomes quickly saturated and cooled to the wet bulb temperature of the entering air.

The saturated and cooled air after passing over the wet bulb thermosensitive element leaves the regulator via elbow 33, which may have an additional turn downwardly or horizontally, before issuing therefrom. The wet bulb thermosensitive element 35, which may be similar in construction to the dry bulb element 23 above described, is mounted on an arm attached to the opposite end of bar 24 from that to which the dry bulb element supporting arm is attached.

In view of the fact that the humidifiers 2 are normally supplied with water at a temperature at or near the temperature of the air of the enclosure being humidified, the wet bulb temperature of the air of the enclosure undergoes little or no change as a direct result of humidification. This is in contrast with the rapid changes in dry bulb temperature of the enclosure which take place as the rate of humidification and its re- 'sulting cooling efiect change. For this reason the Wet bulb temperature remains relatively stable, being affected largely by the rather slow changes in total heat of the atmosphere of the enclosure as influenced by changing weather conditions, sun efiects, heat from machinery and other sources and which affect dry bulb temperature to a much greater extent than wet bulb temperature. Consequently when the wet bulb-compartment once becomes conditioned to the wet bulb temperature of the air of the enclosure, the-wet bulb thermosensitive elements are subjected to relatively small and slow changes in temperature and may therefore be designed and positioned differently from those in the dry bulb compartment with equally good results. Thus the instrument shown contains only two wet bulb cells compared to five dry bulb cells, and the wet bulb cells are mounted in a vertical instead of a horizontal position.

The advantages of the improved and novel construction of the dry bulb side of the regulator herein described will thus be evident to anyone skilled in the science of psychrometry. The most important novel construction features may I be summarized as: v I

a. :Enclosed inner dry b'ulb compartment, in

sulated from the rest of space or otherwise.

b. Separate entrance for an independent current of air to the dry bulb compartment directly and immediately from the enclosure to be humidified.

c. Means such as air nozzle for introducing to the dry bulb compartment air-from the enclosure at a suificiently high and independently controlled rate to insure accuracy and sensitivity.

d. Frictionless poppet valve for controlling regulation air pressure.

It is obvious that details of the regulator construction may vary considerably from the embodiments shown without. departing from the scope of the invention.

A vertical bracket 36, which is mounted, upon the horizontal bar 24 has pivotally mounted upon its. lower end a verticallever 31 against the-side of which the wet bulb element 35 upon expansion exerts pressure to the left as shown in Fig. 2. A spring member 38, which is mounted uponthe upper part of the bracket 36, presses a pin 39 against the lever 31, thereby holding the lever 31 firmly against the wet bulb element eliminating play therebetween and serving to move the lever to the right when the wet bulb element contracts. 7 The upper end portion of the leyer 31, as shown in Fig. 2, is provided with a series of suitably spaced holes and a slide 40 which is adjustably mounted upon the upper end of the rod 31 and is adapted to be secured thereto in any of the holes by means of a bolt and nut 41. Selective adjustment of the slide 4|] may be used where the regulator is set to operate, for example, near relative humidities of 50, 60, 70, or as may be desired for the predetermined condition of the air in the enclosure, additional adjustment for precise humidity level being made at point 84 as hereinafter described.

The upper end of the slide 40 is pivotally secured to a horizontal rod 42 which extends over the dry bulb compartment and is pivoted at its opposite end to an upwardly extending arm of a bell crank lever 43 which is fulcrumed upon an upwardly projecting arm of the weighted lever 26. The horizontal arm 43a of the bell crank lever 43 is provided with a seat which cooperates with an air nozzle 44 extending u wardly from the weighted lever 26 which is supported by the vertical rod 25 extending upwardly from the dry bulb element. A suitable hole in the weighted lever 2ficommunicates with the nozzle 44 and with a flexible pipe of a pneumatic system to control the operation of the diaphragm valves I3 and M in the manner hereinafter described. A modified form of connection between the upper end of the lever 31 and the'rod 42 is shown in Fig. 2b, in whichthe upper end of the lever 31 is provided with a longitudinal slot-and the slide with a bolt extending through the slot and adjustably clamped therein bya nut 3|. Suitable markings along the side of the slot to indicate the position of the bolt for the "the instrument by air predetermined condition of the air in the en'- closure and which will enable more accurate centering than that of the series of bolt holes illustrated in Fig. 2. I

The control valve mechanism I5 of the regu- -lator which governs the operation of the main diaphragm valve. [3 and supplemental valve- 14 in the air line i comprises a horizontal-i:

ped casting having: a.bo y=ll51andnpvar y acso e'za extending: arms-48 and 41 being mounted upon.-

an upward extension of the back plate l9 of the housing, with snap valve mechanism which is mounted: upon the upwardly extending arms 46' and 4-1 for opening andclosing the main valve IS in the air line I and means in the body for restricting. the pressure of the: air in-apneumatic system v for controllingv the: operation of i the snap valve,. and also for continuously controlling. the operationof the=supplemental-valve M; when the main valve 53" open, to: vary the operationof the moisture supplying means in correlation tothe demand: for moisture'b'y the air of the enclosure" to maintain thereina predetermined standard of humidity.

In the controller construction illustrated in Fig; 5,. air under fullpressure is supplied through a: pipe-43 to a horizontal conduit lls whiclrextends lengthwisein the body 45" of the controller: l5,- thencethrough a vertical branch 49a; in the arm- E 'l provided with: a lower chamber 482) and a; cylindrical upper chamber 490'; A tubular valve sleeve 49d;. which is provided with an enlarged head 49%: fitting a countersink in the chamber 490', extends throughthe arm 51' and has an externally screw threaded end having thereon a nut 43? which engages the face of the arm 47 and'in conjunction with the head 49c clamps the valve sleeve firmly in place. The head or the valve sleeve has" an axial passage which terminates ih-aconoidal valve seat 50 for a snap actuated valve'5l having a valve stem m which is mounted-lo'osely in' a bearing member Eib in the valve sleeve and is provided at its end with a double cone 51c adapted to be engaged by snap actuating mechanism hereinafter described. The valve sleeve 49d is provided beyond the valve seat 5% with an annular recess deg which surrounds the valve 5! and communicates with a pipe 52 leading to the diaphragm valve l3 so that when the snap valve 5| is withdrawn from its-seat air under full pressure from the pipe 48 will cause the diaphragm valve '3 toopen.

The base of the controller is provided with a conduit 53 which extends longitudinally thereof in parallelism with the conduit 49 from the lower chamber 495' and is provided with means for restricting the pressure of the airpassing therethrough to the regulator'nozzle 44; to the snap valve actuating mechanism and to the diaphragm valve, I4, all of which are controlled by the conjoint movements of the thermosensitive elements of the regulator.

The pressure-restricting means as illustrated iii-Fig. 5 comprises a rod having an externally screw threaded head 56a which"- is mounted in a countersink in the lower chamber- 4% and has a small axial bore having a removable wire 54b extending therethrough, the size of which wire maybe varied by filing, or otherwise, to adjust the amount of restriction of the air passing through the axial bore in the-rod 5A in accordance with fixed requirements of the particular installation.

A pipe 55, which communicates with the end of' the conduit 53; is provided with a I -shaped fitting from which apipe 56 leads to thesupplementaldiaphragm valve It in the'air line i and also communicates witha pipe 51 which leads through the rear wall [9 of the regulator and communicates with a flexible pipe 58 leading to the nozzle 44 in theweight'ed arm 26 of th'e regulator which is actuated by the" dry' bulb elem'ent 23L The cooperating seat on:v the horizontali arm 63a of the bell crank lever 43 which is actuated by the wet bulb element 351 cooperates in the usual manner with the nozzle 44 on the weighted lever 26 to regulat ethe air pressure in the pipes 58,. 51 and 56,.and thereby continuously to control the opening of valve Mona graduated basis.

The air under pressure thus restricted in the conduit 53' and thuscontrolled' by the regulator isalso employed'to actuate the snap valvemechanism of the controller.

As-shown in Fig. 5 a branch conduit 59 extends upwardly fromthe conduit 53in the vertical arm of the controller which desirably extends across asuitable aperture in the upward extension of the back of thecon-troller casing. The conduit 59 communicates with a chamber 60 of an internally screw threaded boss 60c which extends rearwardly therefrom The cylindrical boss 60a is provided with an axially chambered cylindrical cap Bl which is connected to the boss 60a by a screw threadedconnection.

An expansible bellows 52 having a circular head 63 provided with an integral hub 64 is mounteduponthe upwardly extending. arm 46 in axial alinement-with the bos'sfifla by a tubular screw 65 which extends through the arm 46 and has an externally threaded end portion'which engages internal threads of an axial bore through the hub 64 and has a head 65a which engages the base of the chamber 60 thereby clamping the hub 64 against the upwardly extending arm t6, and also providing a passage fromthe chamber 68 to the interior of the, bellows. The bellows has at its opposite end a head 66 having a hub 61 extending. into. the bellows 62-, A red 68, which extends through and is of smaller diameter than the bore through the screw 65,. has a screw threaded end which engages the hub 61 of the head of the bellows. A spiral spring 69 which surrounds'the rod 68 and is interposed between thebase ofthe chamber 60 and a nut '10 which is mounted on the other endof therod and secured in adjusted position by alock nut H serves to holdthe bellows in predetermined collapsed position against-the restricted air pressure which is suppliedthrough the branch 59 of theconduit 5 3, the chambertfi and thepassage through the tubular bolt 65-tot-he-chamber of: the bellows 62.

The snap valve actuatingmechanism comprises a cylindrical-axially chamberedmember 12 having at one end an annular flange 13 which is provided with an axialscrew threaded bore in which-a screw His seated which is provided with anenlarged-headhaving a central projection 75a which is seated in a complementary central recessin the hub'ii-lof the bel1ows62 to provide aninterlocking: joint therebetween; A- lock screw l6, whichextendsradiallythrough the flange F3 and-abutsagainst the screwid; servesto lock the screw accurately inlongitudinally adjusted posi- $1011;

The. cylindrical wall of the chamber in the member 12 is'provided adjacent its freeend with an internalannular'recess18in which is mounted an annular contractible coiled spring 19 which surrounds and engages the conical end of the double cone 5Ic' which is mountedupon the end of the stem 51a of the snap valve 51. A spiral spring 81-, which encircles the member 12, is interposedbetween the flange 13 on'the chambered member 12 and a nut 8 Which is' mounted on the externally threaded extension of the clamping-nut 49) holds the projection 15a of the screw 14 in interlocking engagement with the-socket in the hub 610i the bellows iiz.- The-bellows 62 is collapsed positionby the 68. The adjustment of the screw '14 and of the nut 10 on the rod 68 is such that the contractible spring 19 engaging the conical end 80 of the valve stem la will normally hold the valve 5! in engagement with its seat 50, thereby preventing the passage of air under full pressure from the pipe 48 through the conduit 49 and branch 49a and snap valve to the pipe 52 which leads to the main valve l 3 in the air line I.

When air under less restricted pressure is conducted from the conduit 53 through the branch conduit 59 and chamber 69 through the passage 65a in the tubular bolt 65 into the bellows 92, the chambered member 12 will be forced longitudinally until the annular spring 19 passes over the rim of the double cone 5lc thereby withdrawing the snap valve from closed position and permitting air under full pressure to pass through the pipe 52 to the diaphragm valve l3 and force the latter to open position.

The restricted air pressure in the conduit 53 is controlled by the conjoint action of the thermosensitive members of the regulator which thus operates to vary the openings of valves l3 and I4 to control the moisture output of the atomizers.

Means for setting the regulators so to control the restricted air pressure as to provide a desired standard of humidity in the air of the enclosure comprises an adjusting screw 82 which is mounted in the wall 29 of the wet bulb compartment and engages at one end a disk 83 upon the outermost cell of the wet bulb thermosensitive member 35 and is provided at its opposite end with an angular head 84 adapted to be engaged by a suitable tool. A disk 85, which is fixedly attached to the adjusting screw 32 and which is located between the wall 29 of the wet bulb compartment and the casing of the regulator, is provided with a circular series of indicia such as 50, 69, and 8!], representing the different settings for desired standards of relative humidity of the atmosphere of the enclosure. These indicia are visible through a suitable hole 85a in the wall of the casing as illustrated in Figs. 2 and 3.

A suitable gauge 86, which communicates with the pipe 51, registers the restricted pressure of the air which controls the operation of the snap valve and the supplemental valve M in the main "air line I, while a similar air gauge 81, which communicates with the pipe 48 indicates the pressure of the air supplied to the regulator.

The regulator operates to control the main valve l3 and the supplemental valve l4 in the main air line I and thereby to vary the capacity of the atomizers as follows:

Assuming that the air in the enclosure is below the desired standard of humidity the atomizer 34 is turned on and saturates and projects a current of saturated air from the enclosure upon the thermosensitive element 35 in the wet bulb compartment of the regulator, thereby reducing the temperature thereof to the psychrometric wet bulb temperature. At the same time air under high pressure is supplied to the air nozzle 2i in the L of the dry bulb compartment, thereby inducing a current of air to flow from the enclosure through the dry bulb compartment of the regulator and to encompass the cells of the thermosensitive member 23 therein. As the temperature of the thermosensitive element 35 in the wet bulb compartment drops, the element contracts allowing lever 31 to move to the right,

' thus moving rod 42 to the right causing bell crank lever 43 to rotate clockwise, which brings seat on arm 43a into near contact with nozzle 44, thereby preventing the rapid escape of air through the nozzle and causing increase of the restricted pressure in the regulator system.

When the escape of air from the nozzle 44 is thus partially prevented the restricted pressure will build up to a predetermined minimum, say eight pounds, and air under such pressure will pass through the branch conduit 59 of the controller into the chamber 60 thereof and therefrom through the tubular screw 65 into the bellows 62, thereby expanding the bellows and forcing the chambered member 12 longitudinally until the coiled spring 19 slips from the conical end 86 of the double cone 5lc over the rim of the double cone and will move the snap valve 5| to open position thereby permitting full pressure of the air from the pipe 48 and conduit 49 to pass through the pipe 52 and move the main diaphragm valve in the air line i to open position, thus letting air under full pressure to flow through the main air line I to the supplemental diaphragm valve l4. As the restricted pressure in the pipe 56 which leads to the supplemental diaphragm valve I4 is at the same minimum the diaphragm valve M will open only sufliciently to permit the atomizers to operate at a low capacity.

If the thermosensitive elements in the regulator act gradually to move the nozzle 44 into closer engagement with the valve seat upon the arm 43a, the restricted air pressure will gradually increase and the supplemental diaphragm valve M will be correspondingly opened, thereby increasing the pressure of the air delivered to the atomizer and the pressure upon the water delivered to the atmosphere and causing the atomizers to operate at progressively higher capacities.

When the humidity of the enclosure begins to rise toward the predetermined standard for which the regulator is set, the wet bulb temperature will remain virtually stationary and the dry bulb temperature will begin to drop causing the thermosensitive element 23 to contract and separate the nozzle and the seat on the arm 43a of the bell crank lever 43 to permit the air under restricted pressure to leak out and reduce the opening of the supplemental diaphragm valve [4 in the main air line I. The regulator system will then continue in balance in accordance with the demand for humidity in the air of the enclosure, the restricted pressure increasing and decreasing as the nozzle 44 and seat on the lever arm 43a are actuated to gradually prevent or permit air to leak out, thus varying the amount of opening of the gradually acting supplemental diaphragm valve M in the main air line I leading to the atomizers. If the condition of the humidity of the air of the enclosure begins to exceed the predetermined standard of humidity the leakage of air through the nozzle 44 will reduce the pressure of the restricted air to such an extent that the spring 19 will be caused to slip over the rim of the double cone 5 l c onto the conical end of the snap valve, thus causing the snap valve 5| to be seated and there by cutting off pressure in the pipe 52 which leads to the main diaphragm valve. The air under pressure in the pipe 52 is then exhausted through the space between valve stem 5 la and its bearing 5lb thus enabling the normally closed main diaphragm valve l3 to close and remain closed until the humidity of the air of the en- 13 means operable by such variation to control the supplemental valve to maintain a predetermined standard of humidity in the enclosure.

4. A system for maintaining the air of an enclosure at a predetermined standard of humidity comprising a horizontal air line supplied with air under suitable pressure leading to an hermetically closed tank, means for supplying water to said tank, means for maintaining the water in said tank at a predetermined level, a pipe leading from said tank below said water level and extending parallel with said air line, a plurality of atomizers mounted on said air line at suitably spaced intervals having means communicating with said air line and having means communicating with said water pipe, a main valve and a supplemental valve in said air line in advance of said atomizers, a regulator in said enclosure having thermosensitive wet and dry bulb elements, means for projecting a saturated current of air upon said wet bulb element, means for causing an independent current of air from said enclosure to flow over said dry bulb element, and means operable by the conjoint action of said wet and dry bulb elements to open said main valve when the humidity of the air of the enclosure is in deficit of said predetermined standard of humidity and thereafter controllably to regulate the operation of the supplemental valve thereby to continuously vary the capacity of the atomizers in correlation to varying demands for humidity by the air of the enclosure accurately to maintain said predetermined standard.

5. A humidifying system having means for vaporizing water and disseminating the vapor thereof in an enclosure with a conduit for supplying water to the vaporizing means, a conduit for supplying air under superatmospheric pressure to the vaporizing means, a main valve in said air conduit movable only to sudden fully closed or fully open positions, a supplemental valve in said air conduit movable gradually toward and from open position, regulating means responsive to changes in humidity of the air of the enclosure, and means operated by said regulating means to cause actuation of the main valve to supply full air pressure to the supplemental valve and to actuate the supplemental valve gradually to control the amount of moisture supplied to the enclosure by the vaporizing means in response to the demand for moisture by the air of the enclosure to maintain a predetermined standard of humidity therein.

6. A system for conditioning the humidity of the air of an enclosure including water atomizing means, a pipe supplying water under pressure thereto, a pipe supplying air under superatmospheric pressure thereto, a main valve in said air pipe movable only to sudden fully open or fully closed positions to control the operation of the system, a supplemental valve in said air pipe gradually movable toward and from open and closed posiitons to control said atomizing means, a regulator in said enclosure having a controller provided with a conduit supplied with air under superatmospheric pressure having a pipe leading therefrom to said main valve, a snap valve in said conduit, and a branch conduit having therein means for restricting the pressure of air passing therethrough, means controlled by said restricted air for actuating said snap valve, pipes leading from said branch conduit respectively to the supplemental valve and to a nozzle in the regulator, a seat in cooperative relation to said nozzle, means in said regulator responsive to changes in humidity of the air of the enclosure and acting to cause relative movement between said nozzle and its seat thereby to vary the restricted air pressure and to cause actuation of said snap valve to open position and gradually to actuate said supplemental valve in response to varying conditions of humidity in the air of the enclosure to maintain a substantially predetermined condition of humidity in said enclosure.

'7. A system for conditioning the air or" an enclosure including water-atomizing means, means for supplying Water thereto and means for supplying air under superatmospheric pressure thereto having a main valve movable suddenly to fully open or fully closed position to control the operation of said system and a supplemental gradually movable valve, a regulator in said enclosure having a controller provided with a valved conduit for air under superatmospheric pressure for controlling the main valve, and a branch conduit having a restriction therein for reducing the pressure of the air passing therethrough, means for conducting the restricted air from said controller to a nozzle in said regulator, a seat for said nozzle, means responsive to the humidity of the air of the enclosure to move said nozzle and seat toward and from each other thereby to vary the pressure of the restricted air, and means operable by such variation to control the supplemental valve to maintain a predetermined standard of humidity in the enclosure.

8. A system for maintaining the air of an enclosure at a predetermined standard of humidity comprising a horizontal air line supplied with air under suitable pressure leading to an hermetically closed tank, means for supplying water to said tank, means for maintaining the water in said tank at a predetermined level, a pipe leading from said tank below said water level and extending parallel with said air line, a plurality of atomizers mounted on said air line at suitably spaced intervals having means communicating with said air line and having means communicating with said water pipe, a main valve and a supplemental valve in said air line in advance of said atomizers, a regulator in said enclosure responsive to the humidity of the air of the enclosure to open said main valve when the humidity of the air of the enclosure is in deficit of said predetermined standard of humidity and thereafter controllably to regulate the operation of the supplemental valve thereby continuously to vary the capacity of the atomizers in correlation to varying demands for humidity by the air of the enclosure accurately to maintain said predetermined standard.

GROVER B. HOLTZCLAW.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 960,830 Cramer et a1. June 7, 1910 1,231,570 Cramer et a1. July 5, 1917 1,819,987 Hodge Aug. 18, 1931 2,292,830 Gauger Aug. 11, 1942 

